Sizing Up Chain

Teeny Tiny

The smallest standard transmission chain is Number 25. The chain pitch is 6.35 mm and minimum tensile strength is 3.50 kN. The smallest chain currently manufactured, although it is not standard, is Number 10, which is used in office equipment. It has a pitch of 3.175 mm and minimum tensile strength of 0.98 kN. There are a lot of micromachines (less than 1 mm) being made, but the chain to fit them is not currently available.

Stupendous

The largest standard transmission chain is Number 240, which has a pitch of 76.2 mm and average tensile strength of 500.4 kN. There are larger chains, but they are not standard. A Number 400, for example, has a pitch of 127 mm and average tensile strength of 1,730 kN. Multistrand versions of this chain are available, as well, from some manufacturers. Their tensile strengths are the multiplication of a single strand. Check with your manufacturer for availability.

The largest chain ever used had a pitch of 1,400 mm. It was created for horizontal rotating parking equipment.

The highest average tensile strength for a single chain—900 tonf—was a block chain. It was used in the production of steel tubing. If this chain were to be used in a multistrand configuration, its average tensile strength would be multiplied.

However, considering the cost, tensile strength of 500 tonf is the limit for a single roller chain.